TIDE:A novel approach to constructing timed-release encryption

In ESORICS 2021, Chvojka et al. introduced the idea of taking a time-lock puzzle and using its solution to generate the keys of a public key encryption (PKE) scheme [13]. They use this to define a timed- release encryption (TRE) scheme, in which the secret key is encrypted ‘to the future’ using a time-lock puzzle, whilst the public key is published. This allows multiple parties to encrypt a message to the public key of the PKE scheme. Then, once a solver has spent a prescribed length of time evaluating the time-lock puzzle, they obtain the secret key and hence can decrypt all of the messages. In this work we introduce TIDE (TIme Delayed Encryption), a novel approach to constructing timed-release encryption based upon the RSA cryptosystem, where instead of directly encrypting the secret key to the future, we utilise number-theoretic techniques to allow the solver to factor the RSA modulus, and hence derive the decryption key. We implement TIDE on a desktop PC and on Raspberry Pi devices validating that TIDE is both efficient and practically implementable. We provide evidence of practicality with an extensive implementation study detailing the source code and practical performance of TIDE

Time-Specific Encryption

This paper introduces and explores the new concept of Time-Specific Encryption (TSE). In (Plain) TSE, a Time Server broadcasts a key at the beginning of each time unit, a Time Instant Key (TIK). The sender of a message can specify any time interval during the encryption process; the receiver can decrypt to recover the message only if it has a TIK that corresponds to a time in that interval. We extend Plain TSE to the public-key and identity-based settings, where receivers are additionally equipped with private keys and either public keys or identities, and where decryption now requires the use of the private key as well as an appropriate TIK. We introduce security models for the plain, public-key and identity-based settings. We also provide constructions for schemes in the different settings, showing how to obtain Plain TSE using identity-based techniques, how to combine Plain TSE with public-key and identity-based encryption schemes, and how to build schemes that are chosen-ciphertext secure from schemes that are chosen-plaintext secure. Finally, we suggest applications for our new primitive, and discuss its relationships with existing primitives, such as Timed Release Encryption and Broadcast Encryption

Improving the Efficiency of Report and Trace Ring Signatures

Ring signatures allow signers to produce verifiable signatures and remain anonymous within a set of signers (i.e., the ring) while doing so. They are well-suited to protocols that target anonymity as a primary goal, for example, anonymous cryptocurrencies. However, standard ring signatures do not ensure that signers are held accountable if they act maliciously. Fraser and Quaglia (CANS\u2721) introduced a ring signature variant that they called report and trace ring signatures which balances the anonymity guarantee of standard ring signatures with the need to hold signers accountable. In particular, report and trace ring signatures introduce a reporting system whereby ring members can report malicious message/signature pairs. A designated tracer can then revoke the signer\u27s anonymity if, and only if, a ring member submits a report to the tracer. Fraser and Quaglia present a generic construction of a report and trace ring signature scheme and outline an instantiation for which it is claimed that the complexity of signing is linear in the size of the ring $|R|$. In this paper, we introduce a new instantiation of Fraser and Quaglia\u27s generic report and trace ring signature construction. Our instantiation uses a pairing-based variant of ElGamal that we define. We demonstrate that our instantiation is more efficient. In fact, we highlight that the efficiency of Fraser and Quaglia\u27s instantiation omits a scaling factor of $\lambda$ where $\lambda$ is a security parameter. As such, the complexity of signing for their instantiation grows linearly in $\lambda \cdot |R|$. Our instantiation, on the other hand, achieves signing complexity linear in $|R|$. We also introduce a new pairing-free report and trace ring signature construction reaching a similar signing complexity. Whilst this construction requires some additional group exponentiations, it can be instantiated over any prime order group for which the Decisional Diffie-Hellman assumption holds

On the Incoercibility of Digital Signatures

We introduce incoercible digital signature schemes, a variant of a standard digital signature. Incoercible signatures enable signers, when coerced to produce a signature for a message chosen by an attacker, to generate fake signatures that are indistinguishable from real signatures, even if the signer is compelled to reveal their full history (including their secret signing keys and any randomness used to produce keys/signatures) to the attacker. Additionally, we introduce an authenticator that can detect fake signatures, which ensures that coercion is identified. We present a formal security model for incoercible signature schemes that comprises an established definition of unforgeability and captures new notions of weak receipt-freeness, strong receipt-freeness and coercion-resistance. We demonstrate that an incoercible signature scheme can be viewed as a transformation of any generic signature scheme. Indeed, we present two incoercible signature scheme constructions that are built from a standard signature scheme and a sender-deniable encryption scheme. We prove that our first construction satisfies coercion-resistance, and our second satisfies strong receipt-freeness. We conclude by presenting an extension to our security model: we show that our security model can be extended to the designated verifier signature scheme setting in an intuitive way as the designated verifier can assume the role of the authenticator and detect coercion during the verification process

SoK: Delay-based Cryptography

In this work, we provide a systematisation of knowledge of delay-based cryptography, in which we discuss and compare the existing primitives within cryptography that utilise a time-delay. We start by considering the role of time within cryptography, explaining broadly what a delay aimed to achieve at its inception and now, in the modern age. We then move on to describing the underlying assumptions used to achieve these goals, and analyse topics including trust, decentralisation and concrete methods to implement a delay. We then survey the existing primitives, discussing their security properties, instantiations and applications. We make explicit the relationships between these primitives, identifying a hierarchy and the theoretical gaps that exist. We end this systematisation of knowledge by highlighting relevant future research directions within the field of delay-based cryptography, from which this area would greatly benefit

Applications of Timed-release Encryption with Implicit Authentication

A whistleblower is a person who leaks sensitive information on a prominent individual or organisation engaging in an unlawful or immoral activity. Whistleblowing has the potential to mitigate corruption and fraud by identifying the misuse of capital. In extreme cases whistleblowing can also raise awareness about unethical practices to individuals by highlighting dangerous working conditions. Obtaining and sharing the sensitive information associated with whistleblowing can carry great risk to the individual or party revealing the data. In this paper we extend the notion of timed-release encryption to include a new security property which we term implicit authentication, with the goal of making the practice of whistleblowing safer. We formally define the new primitive of timed-release encryption with implicit authentication (TRE-IA), providing rigorous game-base definitions. We then build a practical TRE-IA construction that satisfies the security requirements of this primitive, using repeated squaring in an RSA group, and the RSA-OAEP encryption scheme. We formally prove our construction secure and provide a performance analysis of our implementation in Python along with recommendations for practical deployment and integration with an existing whistleblowing tool SecureDrop

DisProt: intrinsic protein disorder annotation in 2020

The Database of Protein Disorder (DisProt, URL: https://disprot.org) provides manually curated annotations of intrinsically disordered proteins from the literature. Here we report recent developments with DisProt (version 8), including the doubling of protein entries, a new disorder ontology, improvements of the annotation format and a completely new website. The website includes a redesigned graphical interface, a better search engine, a clearer API for programmatic access and a new annotation interface that integrates text mining technologies. The new entry format provides a greater flexibility, simplifies maintenance and allows the capture of more information from the literature. The new disorder ontology has been formalized and made interoperable by adopting the OWL format, as well as its structure and term definitions have been improved. The new annotation interface has made the curation process faster and more effective. We recently showed that new DisProt annotations can be effectively used to train and validate disorder predictors. We believe the growth of DisProt will accelerate, contributing to the improvement of function and disorder predictors and therefore to illuminate the ‘dark’ proteome

Transferencia de investigaciones virológicas a sectores educativos y generales de la comunidad

La educación es la única y verdadera herramienta válida, por excelencia, para lograr cambios positivos en la historia, en la política, en la salud o en cualquiera otro aspecto importante de la vida de los hombres. Entonces, deberíamos insistir en mejorar la calidad educativa de los ciudadanos y alumnos de todos los niveles, mejorando necesariamente la actualización de los saberes de los funcionarios, profesionales y docentes para que se inscriba en el discurso cotidiano. El desconocer, no prepararse, nos lleva a crisis sociales que inevitablemente incrementan flagelos como la pobreza, la pérdida de biodiversidad, las guerras, las epidemias, entre otros. Así, desde donde se produce y construye el conocimiento científico, la Universidad Nacional de Córdoba, Facultad de Ciencias Médicas y específicamente el Instituto de Virología "Dr. José María Vanella" también se promueve el objetivo de extensión comunitaria, brindando este proyecto a docentes, alumnos y comunidad en general de la provincia de Córdoba como servicio educativo y actualización. Las temáticas son variadas, los talleres convocan a la Divulgación científica y tecnológica de infecciones virales de importancia sanitaria su conocimiento, prevención y difusión, no solo para el sector educativo sino también para la comunidad en general. Las actividades son talleres, conferencias, laboratorios, jornadas de un día hasta dos semanas. Las metodologías aplicadas son charlas dialogadas, vídeos, dinámica de grupos, Hay evaluaciones de seguimiento a través de comentarios, relatos, encuestas. Todas las actividades de extensión del InViV cuentan con la aprobación de la Facultad Ciencias Médicas a través de las Res. Decanales anuales.Fil: Balangero, Marcos. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Gil, Pedro Ignacio: Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Gil, Pedro Ignacio: Universidad Nacional de Córdoba. Secretaría de Ciencia y Tecnología; ArgentinaFil: Frutos: María Cecilia: Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Frutos: María Cecilia: Universidad Nacional de Córdoba. Secretaría de Ciencia y Tecnología; ArgentinaFil: Díaz, Luis Adrián. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Ré, Viviana. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Farias, Adrián Alejandro. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Spinsanti, Lorena. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Venezuela, Raúl Fernando. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Kiguen, Ana Ximena. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Konigheim, Brenda. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Pisano, María Belén. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil:Masachessi, Gisela. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Barril, Patricia Angélica. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Varella"; Argentina.Fil: Barril, Patricia Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Castro, Gonzalo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Batallán, Pedro Gonzalo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Batallán, Pedro Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Quaglia, Agustín.Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Tauro, Laura Beatriz. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Tauro, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Flores, Fernando Sebastián. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Flores, Fernando Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Beranek, Mauricio. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Beranek, Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Maturano, Eduardo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Rodríguez, Pamela Elizabeth. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Cámara, Jorge Augusto. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil, Albrieu Llinás, Guillermo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil, Albrieu Llinás, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios en Comunicación, Expresión y Tecnologías; Argentina.Fil: Adamo, María Pilar. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Ghietto, Lucía María. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Ghietto, Lucía María. Universidad Nacional de Córdoba. Secretaría de Ciencia y Tecnología; ArgentinaFil: Pedranti, Mauro Sebastián. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Giordano, Miguel Oscar. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Martínez, Laura Cecilia.Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Isa, Maria Beatriz. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Ascheri, Stella Maris. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Paredes, Norma Gladys. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Contigiani, Marta Silvia. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Benítez, Marta. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Theiler, Gerardo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Augello, Marysol. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Fosatti, L. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; ArgentinaFil:Moreno, F. Colegio San Martín; Argentina.Fil:Marín, M. Colegio Nuestra Señora del Sagrado Corazón; Argentina.Fil: Carreras, G. Provincia de Córdoba. Ipem 323 de Villa Angelelli; Argentina.Fil: Navarro, A. Provincia de Córdoba. Ipem 323 de Villa Angelelli; Argentina.Fil: Fuentes, M. Provincia de Córdoba. Ipem 323 de Villa Angelelli; Argentina.Fil: Santiago, T. Provincia de Córdoba. Ipem 323 de Villa Angelelli; Argentina.Fil: Cámara, Alicia. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Paglini, María Gabriela. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Cuffini, Cecilia. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Gallego, Sandra Verónica.Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Aguilar, Javier. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Paván, Jorge. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Fil: Nates, Silvia Viviana. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Virología "Dr. José María Vanella"; Argentina.Enfermedades Infecciosa

Critical assessment of protein intrinsic disorder prediction

Abstract: Intrinsically disordered proteins, defying the traditional protein structure–function paradigm, are a challenge to study experimentally. Because a large part of our knowledge rests on computational predictions, it is crucial that their accuracy is high. The Critical Assessment of protein Intrinsic Disorder prediction (CAID) experiment was established as a community-based blind test to determine the state of the art in prediction of intrinsically disordered regions and the subset of residues involved in binding. A total of 43 methods were evaluated on a dataset of 646 proteins from DisProt. The best methods use deep learning techniques and notably outperform physicochemical methods. The top disorder predictor has Fmax = 0.483 on the full dataset and Fmax = 0.792 following filtering out of bona fide structured regions. Disordered binding regions remain hard to predict, with Fmax = 0.231. Interestingly, computing times among methods can vary by up to four orders of magnitude